PoissonBayesMixedGLM.
logposterior
The overall log-density: log p(y, fe, vc, vcp).
This differs by an additive constant from the log posterior log p(fe, vc, vcp | y).
statsmodels.genmod.bayes_mixed_glm.PoissonBayesMixedGLM.from_formula
statsmodels.genmod.bayes_mixed_glm.PoissonBayesMixedGLM.logposterior_grad